Differences in preservation of canine chilled semen using simple sperm washing, single-layer centrifugation and modified swim-up preparation techniques
J. Dorado A E , M. J. Gálvez A , S. Demyda-Peyrás A , I. Ortiz A , J. M. Morrell B , F. Crespo C , J. Gósalvez D and M. Hidalgo A
+ Author Affiliations
- Author Affiliations
A Animal Reproduction Group, Department of Animal Medicine and Surgery, Faculty of Veterinary Medicine, University of Cordoba, Campus de Rabanales (Edif. Hospital Clínico Veterinario), Ctra. Madrid-Cádiz, km 396, 14071 Córdoba, Spain.
B Department of Clinical Sciences, Division of Reproduction, Swedish University of Agricultural Sciences, Ullsväg 14C, Box 7054, SE-75007 Uppsala, Sweden.
C Veterinary Services of the Spanish Army (FESCCR-Ministry of Defense), C/Arsenio Guitiérrez Palacios s/n, 05005 Avila, Spain.
D Department of Biology, Genetics Unit, Autonomous University of Madrid, 20849 Madrid, Spain.
E Corresponding author. Email: jdorado@uco.es
Reproduction, Fertility and Development 28(10) 1545-1552 https://doi.org/10.1071/RD15071
Submitted: 21 November 2014 Accepted: 24 February 2015 Published: 17 April 2015
Abstract
This study compared the efficacy of simple sperm washing (SW), single-layer centrifugation (SLC) and modified swim-up (SU) techniques in the preparation of dog spermatozoa for cooling. Eighteen ejaculates, collected from three dogs (six per dog), were pooled (three ejaculates per pool) and divided into three aliquots: (1) one aliquot was washed and cooled at 5°C for 72 h, considered as control (SW-control), (2) the second aliquot was selected by SLC through Androcoll-C and subsequently cooled in the same way as the SW-control samples (SLC-AC) and (3) the last aliquot was selected by a modified SU method with Androcoll-C and cooled as mentioned above (SU-AC). Assessment of sperm motility, sperm morphology, sperm membrane integrity and acrosome integrity were performed on aliquots of fresh semen and chilled–rewarmed samples. Sperm membrane integrity and progressive motility were significantly (P < 0.05) improved by SU-AC compared with SW-control. Morphological sperm abnormalities decreased significantly (P < 0.001) in SLC-AC samples compared with SW-control samples. These sperm variables did not differ between SLC-AC and SU-AC methods (P > 0.05). The recovery rates were not significantly (P > 0.05) different between SW-control, SLC-AC and SU-AC samples. Our results confirm that SU-AC may be a successful method for the preparation of dog spermatozoa for cooling.
Additional keywords: Androcoll-C, chilled dog semen, colloid, sperm migration, sperm selection.
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